Does avg product scan at re-boot?

If a scheduled scan was missed while the system was shut down, then yes - unless you deselect the setting highlighted in this screenshot:

User-added image

Thanks Bruce,
I'll check out the setting.

Does AVG product scan when system boots up?

Thanks Bruce,
I'll check out the setting.

If a scheduled scan was missed while the system was shut down, then yes - unless you deselect the setting highlighted in this screenshot:

User-added image