I have also thought about that, and damn sure Maxis has also saw the loophole.

Thus

your plan won't work (at least not fully)

because

NOW at present, Hotlink Share-A-Topup or Ask-A-Topup can only performs max RM20 transactions per day, and max RM100 per month.

So if you want to transfer RM100 from one hotlink to another, you have to do 5 times over 5 days, and with costs of (RM0.50 x 5 times)

As far as I recall from when I first subscribed, it does stack though there must be some limit.

However, because there is the rule that you have to top up minimum RM30 in the first 6 months of the 365 days term, then I do not recommend topping up RM100 beforehand.

#hotlink is the only plan right now for new activations and port-in. I am trying to persuade Maxis to add an alternative prepaid plan that's optimized for call and SMS.

Indeed, it is still cheap...
all in
70 days of Free internet  would costs RM7.50 (i.e. RM3.21 per month)
but with certain drawbacks
a) have to maintain 2 sim
b) suppose SIM 1 - old Hotlink plan with Hotlink 365/Activ10 numbers for calling
c) SIM 2 - #Hotlink plan for free internet every 10 days
d) hassle to do the transfer every 10 days

I think with the credit in SIM 2 - the money is safe there, cause once the line is inactive - you can't use the internet and thus not charged per kb <----- NOT SURE, have to confirm. Don't want a situation where I forget to do the transfer to keep SIM 2 active, and have it eat all the credit inside.

==================
As for me, saw the opportunity to have free internet albeit at 64kbps  for a full one year 365 days + 100 days with my old Hotlink plans(in deactive period).
- top up RM100 get 100 days active + extra RM5
- subscribe to Hotlink365 (RM33) so that adds 365 days to 100 days
- upgrade to #Hotlink plan (RM5) and have 365 days+100 days of free internet.
- transfer out any leftover credit to other old Hotlink numbers which doesn't want to migrate to this #hotlink plan.

Not bothered with losing out on Activ10 - as phone seldom make calls , further more it is an Old Extra Plan, where the call rate are very expensive. So this #Hotlink call rate better for my case. But the call rate is definitely not good for those who utilizes the Activ10 numbers often.

Also not bothered with losing out on the Hotlink365 at the end of the (365 + 100 days)... can MNP out, or maybe things will change after one year whereby all telcos will give free basic internet... 465 days is a long time.

Although RM3.21 per month is good, I have heard of other MVNO that can provide affordable deals <RM8 per month unlimited with 600MB @ 364kbps with One year validity as well.  But it seems only ppl with access to Genting Casino can apply.  Dunno if the deals are still valid today.

if buy topup frm u sure will save more 

Surprise... Surprise...
You wouldn't believe what I read in the maxis forum.

previously my sister told me need 3 months tenure with maxis was on 29/11 and WaCKy-Angel reported the same on 9/12.
however, myself379 reported on 14/12 that it's now 6 months tenure with maxis, instead of 3 moths.

that's yet another great plan from you! +1   

but as per inform my many users (including my sister), now #hotlink still allow users to use the unlimited internet even though their validity has expired. 
so basically users now not even need rm2 per month yet (as per your idea). 

I'm currently on a Hotlink365 plan, will the application for the free 64Kbps internet end my Hotlink365 plan?