When the digits died on my Honeywell I replaced it with this ... https://www.wolseley.co.uk/product/center-7-day-programmable-room-thermostat-230-v/ Cheaper and better.
Remove stack and grey pipe trap. Fit this ... https://www.screwfix.com/p/mcalpine-appliance-trap-white-40mm/81714#product_additional_details_container Washing machine outlet fits to spigot so one trap does it all. Quality parts.
I still watch JC's TG on Dave just to remind myself how good the content and production was .I still find it addictive viewing. Paddy ****ing McGuinness is stretched just doing bingo adverts.
Use a resin bound kit, no loose stones for the little scotes to put through your windows ... https://www.vubaresinproducts.com/resin-bound/resin-bound-kits.html
Personally I would drill a hole through the post and brickwork that is the same diameter as the shaft of the bolt leaving the threads to cut their own way for a tight fit.