My 2 cents.
Covid made every department work at probably 60-70% of productivity due to many logistical issues. And as per as DHA is concerned, immigration is one of the many responsibilities it has in hand.
Of the 60-70% of productivity, majority be going into 1.day to day emergency activities 2. COVID related stuff (govt tends to utilise resources across different activities during pandemic situations). Managing travel, quarantine and addressing the queries who are abroad(residents &citizens and their family members)
Considering all these, they would have spared 2-3% effort on immigration related activities(PRs). These limited efforts are primarily going into critical applications.
PS: These are my views. Mostly based on what i read, comprehend and imagine. I dont have any contacts at any level.