If you read beyond the head note in Bhavsar (late application for PTA: procedure : South Africa) [2019] UKUT 196 (IAC) (12 April 2019) you will see that the Tribunal look at rule 33(2) FTT procedure rules which states:
(2) ... an application under paragraph (1) must be sent to the Tribunal so that it is received no later than 14 days after the date on which the party making the application was sent the written reasons for the decision.
Looking at the way the Tribunal calculate the 14 day time limit (see paras 27-29) it seems that the day of sending should be counted as day 1 for working out the 14 days.
Forgive me if this is old news but it is worth being aware of so that your grounds are not being rejected as being out of time.