cable from here to november ?

I am emigrating to the US in November - I have opened a $ account in the Isle of Man - when should I buy $ (sell gbp) and at what price points ...

I have already bought 20% of my needs at 1.9970 ish

I am absolutely incapable or predicting where price will be in 4 months time. In fact, I have no idea where it will be tomorrow.

But my weekly GBPUSD chart says bullish...