The critical thing is to show real evidence that she will return to Thailand. A credible employer letter making it clear she must return after her 'holiday', and/or birth cert of her child(ren), and/or copy chanote of property she owns. Without those your invitation letter is immaterial, imo.
seems to depend on the office - and may be officer, time of day etc! I am long term resident and CM Imm declined my 90 day as I had stayed at a hotel down south since previous 90 day and not filed new tm30.
it was for me until they tripled my premiums,despite no claims. My 'misdemeanour ' was a birthday which Cigna said put me in a higher risk pool. I cancelled. Of course.
I only know of one case with Chinese owner and tenant in Chiang mai. Tenant had all necessary docs but was refused and owner had to attend, for initial tm30 to be issued. Not sure if that is general at CM Imm.
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