No Lollipop for you! HTC One mini 2 will not be updated
According to the message that was sent from HTC's Twitter account, "We determined that Lollipop on the One mini 2 will not provide an optimal experience; it isn't scheduled to receive the update." HTC's Mo Versi tweeted back in March that only the Google Play edition of the HTC One (M7)would be receiving an update to Android 5.1. HTC had guaranteed that the model would receive updates for two years from its launch date, but that time period had expired. A subsequent text from Versi hinted that HTC brass was reexamining the situation.
Back in the summer of 2011, HTC originally said that it would not update the HTC Desire to Gingerbread (Android 2.3) due to the lack of storage space on the handset. The manufacturer had originally said that the model would be receiving the update. A few days later, a tweet from HTC tersely announced that it had changed its mind once more and the HTC Desire was once again scheduled to receive Android 2.3.
Considering HTC's history of flip-flopping in similar situations, HTC One mini 2 owners should probably wait a week to see if the company changes its mind.
source: Reddit via AndroidAuthority