Migrated DB Host name changed again

[#1]

My scripts which I finally got working after migration .... no longer work since yesterday.
 
After migration, MySQL manager  listed the DB host details as:
sqlc51.megasqlservers.eu         and today MySQL manager shows
sql5c51a.megasqlservers.eu
Any ideas why this has happened ?
Anyway, fixing the host name makes my site work again.
However, All my data after 28/10/2013 has been lost 

[#2]

sqlc51 is the mysql4 database server whereas sql5c51a is that for mysql5. phpMyAdmin has problems accessing mysql4 databases so perhaps Hostopia are moving users with mysql4 databases to mysql5 equivalents. However in the absence of any communication one can only guess.

[#3]

The problem's almost certainly related to this.