When to step up the intensity for young swimmers?

I'm sure this issue comes up a lot - and there probably isn't a 'best' answer... but I'm curious all the same (and I'm going to apologise now for the long post... if you get all the way to the end, you get a gold star!)

My son has just started 'competing' this year - he just turned 8yo in September. He's been having swimming lessons since he was 6 months (plenty of good programs here in Australia for that, starting with pool safety, going through all the stroke development etc.) - he doesn't do squads yet, so the amount of 'training' (probably not the best word to use here) is pretty light. He currently does (each week):

(in the pool):
Monday:
* School swim lesson: 30 mins (basic stuff as most kids in early primary can barely swim - that's only 1 term/year)
* Main swim lesson: 45 mins (I think they usually cover around 750m all up + work on turns etc. - runs pretty much all year)

Tuesday:
Swim club: 4 races (mostly 25m, but doing 50m free; October-March)

Apart from that, general 'kid' stuff in the backyard pool (plenty of that at the moment just coming into summer here), and the occasional extra bit of stuff here and there.

Out of the pool, he also does Tennis 2 days a week.

Now, that's not a lot of time in the pool (given some of the stuff I read on here) - the next step up for him is 'mini squads', where he will go 2-3 days per week for 1 hr at a time (I think), there are kids his age already doing that, but some older ones competing quite well who haven't gone down that road just yet either.

My question is when do you think it is best to start stepping young kids up to these levels (and beyond - the older kids obviously train a lot more than that again)... I've seen arguments both ways (more hours in the water = more improvement vs avoiding burn out / don't over do it / technique first etc.)

A few points about my son in particular (as I know everyone is going to be different to some degree):

He's only started racing at swim club during the last two months - his freestyle technique is outstanding (could just be proud parent talk, but he just glides through the water). backstroke was good 12 months ago but he lost his way with it a bit and is just getting it back now. butterfly, he needs to build his core strength a bit more but is improving quite quickly and breaststroke... well, best not to talk about breaststroke right now :)

We've taken him to one swim meet so far - he just swam 50m freestyle and 50m backstroke and got a qualifying time for the regional champs in freestyle (was 1 sec out for backstroke) - regionals are in Feb. He's improving his PB's in at least 1 stroke every week at the moment and we'll probably take him to another swim meet mid-Jan to get qual times in backstroke and butterfly (butterfly has only really just come on in the last couple of weeks - down to 26.50 for 25m last week, breaking his PB by 2.5sec)... though I'd be happy for him to just swim freestyle at the regionals - really just going to show him what to expect from a big event etc.

If he continues to improve close to his current rate, he could be down to about 44s+ for 50m free at the regionals - that'll probably be around 5-7s off the top swimmers for his age group, a fantastic effort by any stretch (heck, the 47s he's swimming now is a fantastic effort). The really interesting meet will come in August when they have the regional short-course champs, that's another 6-months of development and only 1 month before he turns 9... I don't think he'll quite be pushing for a medal, but he could go pretty close (depends how much swimming he gets in over winter I guess).

Now there's probably no reason why we couldn't start him swimming with squads right now - he loves training, but he can push himself too far at times - when he sets a goal he's very focused on getting it. Countering that I think he gets better input on stroke development with his current class structure than he would get in the mini-squads and there's also the time pressures on mum - adding another 1-2 afternoons a week shuttling back and forward to the pool (I know that's only going to get worse, but parental burn-out can be something to watch too!).

...so - still with me? definitely a gold star if you've read this far! our current thinking is that we'll keep going as we are at least until swim club starts up again next year (so Oct, just after he turns 9), then start increasing the amount of time in the pool from there depending on where he's at and what the head-coach thinks etc. While his times keep improving, we probably don't need to increase his workload too much at all, but once things start to plateau off I guess it makes more of a difference.

So what would you do? he loves swimming, he's ultra competitive, he loves training / exercising / playing any sport.. but he's also very much in 'kid' mode as you would expect - I don't want him to be obsessed by training etc. (not yet anyway) but I want him to be able to say he achieved his 'best', and - proud parent talk here again - I think he has the potential to be quite good, but I don't think he would ever reach his peak as an 8yo - he's not 'big' for his age, but he's always up there ability-wise in any sport he does.

Thanks

Thanks Meisam - and just as an update he's still progressing really well, has just increased his main swim lesson to 1x45min lesson per week (was actually only 30min stroke development lesson up to a few weeks ago), but his 30min swim lesson at school will at least be useful for the next couple of months as his teacher is giving him a special program and just has him doing laps basically (did 300m freestyle in his school lesson last week).

...and after having two months away from club night comps over the holidays, he smashed his PB by about 3.5 seconds (almost exactly two months between races, 50m free: 43.3s) in a regional level meet a week ago and finished top 20 (very competitive metro region) and gets to race most of the same kids again in a couple of weeks.

Just have to work at getting his other strokes up to scratch now... Backstroke is nearly there, Butterfly needs some more core strength, but Breastroke... let's just say that one hasn't shown signs of clicking yet - if he did do more training I guess that's where the main benefits would lie, but there is plenty of time to develop them.