Maybe some of the reports of increased air traffic at Erebuni are touch-downs/refueling of aircraft en-route to Syria bases.
A side note...I was surprised Russia flew the "White Swan" on bombing flights over Syria. And the Swan flew all the way from the Kola Peninsula.
“Putin has big plans for Erebuni.”
As part of the former Soviet Union, no doubt there are lots of old ties and habitual relationships that could be exercised between Russia and Armenia - especially against Turkey. Armenia has good reason to fear Turkey, and Russia is perhaps their best ally to deter Turkey.
If Turkey and Russia seriously get into it, Armenia has lots of Turkish speaking people and connections to exploit for intelligence purposes. Also, the border with Turkey would allow for military supplies to be smuggled to the Kurdish minority (~20% of Turkey’s population), if they chose to foment an uprising. There remains an Armenian minority in Turkey as well.
The Soviets no doubt built infrastructure in Armenia (then the Transcaucasian SFSR) to support war plans against Turkey over several decades.
Even if it is only to support Syrian air operations, supplies could be forward positioned overland for faster turnaround, and emergency airfields would be needed along the routes (without having to depend excessively on Iran).
Russia seems to be testing and exercising a lot of its top shelf gear (tanks, jets, missiles/rockets), as well as their strategic air in Syria - great training, as long as there are no combat losses. Their bench is not deep like it was in the Soviet era, the number of aircraft is much lower. Their top line strategic bombers are individually named, like our aircraft carriers.