For example ID1 will provide 2 on off sequences for both hot water and heating separately at different times Mon- Fri and Sat and Sun.

I have no special electrical knowledge but based on my background reading I just switched the power off at the mains, swooped the controller, and switched the power back on. I do not have any of these, but the manual mentions EP2000, EP2002, EP3002 and EP6002 so I guess all of those are just as easy to replace with the EP2. Not sure what the problem is but wondered if it's reasonable to think that it's a fault with the programmer so, if I'm going to change it, then to opt for the EP2? Some say that it's an ideal direct replacement and that it works seamlessly with their existing boiler.

Finance is provided by PayPal Credit (a trading name of PayPal UK Ltd, Whittaker House, Whittaker Avenue, Richmond-Upon-Thames, Surrey, United Kingdom, TW9 1EH). The instructions look a bit daunting, but all you really need to do is to set the programmer for your preferred time sequence. Praise the Lord, I had visions of having no hot water and a grumpy wife nagging me to get a whole new boiler for days. Had to push it down quite hard to lock it in place, as the wires behind had to be pushed back, but it sprang into life when I powered back up, and after I'd programmed in the ons and offs took over where the old had left off. I carefully cut the central support out and discarded it; this allowed me to push the wires back into the pattress and the programmer to fully locate on the backplate.

Keep hitting the Yes button to go forward after the times have been set up but do not seem to get the actual day of the week to set up for Sat and Sun. They mention that it is an excellent replacement for their old or broken predesessor, and it easily replaces the previous model.

Gone through the instruction sheet but it is not clear when or how to access just the individual days.