CL doesn't allow me to port back the line from MR hence checking if there is a minimum cool down period
Did they say no right where you entered your number ?
If you get a response almost immediately, I suspect this is the reason :
There is some mention that a number can be only ported once a month, not sure if it is a generally porting rule or specific to certain telcos. Also is once a month is referring to calender month or what.
Beyond that the transit telco can impose minimum subscription period, eg Simba & eight is 30D. CL told me early next month. Maxx is supposedly anytime, but could be subjected to the once a month thing mentioned above. It appears to be possible to get the telco to waive off this requirement if you can justify it.
Kelvin is probably the expert on this matter.