Disclaimer: I'm generally conservative with trades early and target the bye rounds.
32 trades between rounds 1-19
You can trade 4 per week from round 13 onwards
4 extra trades kick in from round 20
Say you want to go hard at both bye rounds, you would probably be looking at 4 trades each week from 13-16 = 16 plus probably 4-6 to use either side.
My point is that to Target the bye rounds hard I need to save at least 20 of 32 trades. That leaves me 12 for rounds 1-12 and rounds 18-19.
I don't think it matters where you use your trades, but if you are going hard early you'll need to hold trades for a little bit somewhere before round 12.
For my team (based on official BEs):
Bully has a BE of 25 - if he matches his 20 last week he loses $5K - I'm having another look
Tuilagi loses no money this week, I'm waiting for next week
Nanai has a BE of 28, it's plausible he could exceed this and probably won't drop cash
Leniu - My last minute week 1 mistake has a BE of 12, will likely make cash
Ilias is the one I have the most concern about but I want to give him another week
I luckily started with both Kings
If I want Starling in one trade I'd have to let go of Sam Walker, and I don't think it is worth the trade, at this point, to punt that Starling will make cash over Walker, when the Roosters could improve.
So I'm holding trades, but I know this means I'll have no cash for Cleary and it will take a bit longer for me to get him in. I'm also missing Starling this week, and it is likely I'll have to miss Thompson too. But, you can't get everyone.