Change or upgrade to parts mid season

[hibble]

Quick question, can Formula 1 teams change or upgrade parts at any point through out the season or are there set points though the season this can be done, for some reason i seem to think that there is a point in the season where upgrades can be implemented. Any clarification on this would be much appreciated.

[NathanOlder]

Teams can update the cars as and when they like, Teams often bring new parts to most races, Teams try many new parts on the same day. Friday practice is almost like a new parts test session at times.

[bhall]

There was once a time when even engines could be updated at will. Anyone remember that?

[Richard]

Friends can update the cars as and when they like, Friends often bring new parts to most races.....!!!

Sometimes spambots have a quaint view of F1!

(Original post and account deleted)