Hi Ana,
Save the script with warning, the value of the variable (%MONTHS_ALL%) will be determined after execution of the script, hence the warning.
Another point, in you REC statement, "*EXPRESSION=%VALUE% " is not required, just omit it. For e.g.,
*REC(ACCOUNT="PGTOIMP_221001", TIME=TMVL(1,%TIM%))
would be enough.
Regards,
Kalyan.