I stay 6 months in two 90-day blocks each year. I get a multiple entry non-imm O visa (over 50 with state pension) from the UK. This gives a 90 day stay every time I enter during the one year validity of the visa.
Keep up the good work, Tod.You have been an invaluable source of accurate visa info, to me and many others, over many years. So sorry you have had hassle with a group member. I hope he/she is removed. There is no place for such harassment in this group.
I believe the UK embassy only touts the single entry non-O. However, when you apply online, the drop down list shows multiple entry. I just clicked on that and it worked, no need for any special 'proof' either. Maybe I was just lucky but I'm not knocking it.