Can you *GUESS* what happens when you take an 8-digit local number,
> prefix it with the Helsinki city code ('0'), prefix that with country
> code 358, and show only the last 10 digits?
Helsinki changed its code from 0 to 9 when the access code changed the other way -- 9 to 0. I think it's more likely that the OP is seeing a national number with the international flag set en route, perhaps it's a French or Spanish "derived"/"virtual" number or a bad presentation number.
In many countries national calls are routed abroad and back to take advantage of settlement rates. This can cause local numbers to be sent with mixed flags and truncated lengths. But we can only guess unless the OP can nab the caller the next time.
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