I share bic bashers 2 minds. I have a hidden disability that makes bith ticket machine and websites difficult.
I have elderly freedom card but struggled to buy tickets to extend my journey out of the freedom pass area. Ticket offices can be easier.
They tend to go in waves... Looking at https://www.southernrailway.com/travel-information/plan-your-journey/planned-engineering-work for July gives
No trains 1/2 July
No trains 15/16 July