Right, for UKARA it's 3 times in OVER 2 months and less than 12.
Most companies wont let you have UKARA/Site membership with them if you go to multiple sites ( thats not saying you cant play other sites, that's fine but for site membership qualification purposes they like to know you are using them regularly, normally to keep it live many ask you play there once or twice a year from that point) unless they are all owned by the same parent company, eg, playing any UCAP site, Sandpit/Greenops/TheBunker.
Although for my example UCAP aren't fans of UKARA and simply being a member of a site is enough of a defence, when you want to buy a rif simply give them your site membership number and tell them who to call, they call the site owner and ask if X plays there regularly and site owner say "yeah sure I know X great guy sell him a RIF".
The UKARA number is your site membership number, they use a three letter and I forget how many numbers system. Mine was UWGxxxx but it lapsed as I stopped playing at that site, I could have got UCAP to do it retrospectively but at the moment its stopping me buying any more RIFs. I will shortly be starting playing at Gunman sites and I may then decide to get them to do mine.