100% agree with your wording of the proposed changes.
Expiration of votes and proxies, based on time.
Notifications on UIs (front ends and in wallets)
& if I may make a suggestion, that the term (time length of vote validity) be 365 days.
That seems to have been a rather amicable figure when mentioned in various witness chats in the past. Although no exact time frame was ever agreed upon by all people in those public live podcasts.
Fully support you putting this out publicly, openly and transparently.
If applied in HF25, would you be in favor of retroactively applying it or do you think it should start counting 1 year from HF25's date?
In order to ensure the safety of the chain, the datestamp of the cast vote, namely the day and month (not the year) should be the date from which the ticker starts its countdown after HF25.
i.e. if a vote was cast on 01 August 2017 then the ticker will retroactively start its countdown on that one witness vote from 01 August 2020. (assuming HF25 is done before 01 August 2021)
So "retroactively" is the answer, but in no way all from the same date, as that could risk the chains existential security in 365 days from that common date it started.