I would like to share my experience as it could be of some help. I did my masters from a top university . Got into full time job . Filed my intial h1b in 2014 . I had to resign my job in march 2016 and was out of status for three months . Filed a h1b with a consultancy just to maintain status that too filed it on 89th day with normal processing. Got a new job the following week and they filed it in premium . Got RFE about maintainance of status. Submitted necessary proofs . H1B approved but mentioned ineligible to extend the status because there is a gap in status . Had to go to consular processing . In the rfe response , mentioned that will be able to go to Tijuana Mexico if necessary for consular processing . I797 has information that my file is sent to Tijuana . Booked the slot and went for stamping . No need to have any mexican visa . One day for finger prints , on the main visa interview , asked questions about job , took my passport and told me that they need furthur verification and asked me to check back next day. I didnt get any 221g form . Its just word of mouth . Next day they said everything looks good but passport is not ready . I picked my passport the following day .
Suggestions :
Do not have a gap in H1B status
Do not trust any company or consultancy that says its ok to be out of status
Especially consultants at any cost be on payroll .
Going for stamping to mexico or canada is not easy if you have issues like this.