Can't reach UM, can't reach my UM UK number, no reply to e-mail

[andy]

Originally Posted by prion

I have realized that cheap callthroughs (below 10p/min) in the UK do no longer offer calls to +4236 mobiles.....

Even when they did have calls for 10p, they weren't reliable.

Several providers told me there is a large gap in price between the cheapest and next cheapest wholesale carriers, but also a large difference in quality. This was true 4 years ago, and still seemed to be the case more recently if trying via a 10p (from landlines) 0871 number. But with time most providers either shifted to tariffs in the range 15 to 30p, or stopped providing the destination if their particular method wouldn't cover rates that high.

I don't think any of that implies clues to what is happening at the other end now.