that is the plan 
every monthly cash transfer to IB results in full balancing, since the transfer amount is (in my current state) far bigger than the course changes between my 5 funds. as you can see here, each trade costs me on average USD 0.3, regardless of the trade volume. for the next year, until i reach CHF 100’000 and the monthly fee of $10 applies, my additional costs for each trade will be virtually zero. bottom line, rebalancing costs about nothing. I also dont rebalance amounts smaller that USD 200, and this thresold will increase in future, to still keep commissions low.
Now when my monthly cash feed won’t suffice to rebalance, I will have to come up with a rule. probably a full rebalance after each 6 or 12 months or when the allocation percentages deviate 2-5percent points from their intended values