It's technically been used more than three times though? (even if you count the return journey as part of the original)
Maharani time travels
Maharani time travels back with Ravi.
Tara's Radha-Krishna dupatta time travels
Tara time travels
Dharmendra time travels (remember that at this point, it was also said that folks were very of Navrangvan because people simply used to disappear, so more people have definitely used the portal)
Tara and Dhruv time travel back
Dharmendra's weekly okay messages (and we know it's atleast a month since D-T travelled)
Peti being sent empty.
Oh yes you are absolutely right, it did happen more than three times. Also looks like they will travel one more time.
I don’t the portal to be used as public transport though that anyone can TT. Right now only family knows and Dharmendra - but I hope it’s not free for all thing.