IMO the longer you can run the hcg along with the cycle the better. Holding off the tren ain't going to matter much, as test is gonna shut you down fast anyway, with or without the tren. There isn't a downside really to starting hcg 4 weeks in, many just do the last 2-4 weeks of the cycle. Its good you ask intelligent questions, because being cautious will save you in the end.