You might want to include a description of the numbers station, so we can tell which one you mean.
Right now (1745 UTC, the same day) I have the Cuban station HM01 (alternating Spanish numbers and digital data) on 11530 kHz in AM mode. But nothing unusual about that, it is one of its scheduled frequencies and times. HM01 carrier turned off at 1750:55 UTC and it will be going to 11635 kHz for its next transmission, starting at about 1800 UTC (normally starts several minutes early).
T!