HCG aids recovery.
Your eating and training will have a bigger impact on wether you keep the gains, make sure you eat like a pig during and after PCT
The reason why i thought your starting PCT 4 weeks after your cycle is because in the original post you wrote
test e 1-12
Pct 16-19
Thats a 4 week gap?
You should start PCT 10-14 days after your last Test E shot, not 28 days