The JAK2 mutation can cause increased myeloproliferation in any of the blood cell lines. A temporary increase could be the result of an infection. A sustained increase in your blood cell values may indicate a change in the status of your PV.
It would be best to discuss your increased monocytes and granulocytes with a MPN Specialist. Hopefully, you are already consulting with a MPN Specialist rather than a regular hematologist about your case. Juts in case you have not seen the lists, here are some resources.
https://mpnforum.com/tsr-the-list/
https://www.pvreporter.com/mpn-specialists-canc...

MPN Specialists | Cancer Treatment Centers | PV Reporter

https://www.pvreporter.com/mpn-specialists-cancer-treatment-centers/

TSR — The List

https://mpnforum.com/tsr-the-list/

I have learned over the years that various blood levels show a bit high or a bit low, some consistently while others come and go.

Always look at your lab and other test results, and ask your physician about anything you don’t understand.

All the best.

Mine too with ET. I wonder why.

Thank you