G-Sheets Script: Auto-Send Email 24-hrs Before Different Deadlines

Hi guys, so I know there are many different guides how to send auto-email reminders from Sheets with add-ons but none of those I can apply here. Some help with a script, please?

1. I basically have days set to MON, TUE etc in column A

2. email addresses are in column W

3. users should receive an email reminder 24-hrs before preset deadline.

4. the 24-hr trigger set as:

- if column A is MON, email the reminder at 3pm on SATURDAY
- if column A is TUE, email the reminder at 3pm on SUNDAY
- if column A is WED, email the reminder at 3pm on MONDAY

and so on...

IMPORTANT: I travel, so Ideally, and if possible, the trigger should fire off my local time instead of some fixed timezone. can Sheets pick up time from a current location on my laptop? and if not, it's ok to have it triggered on a fixed timezone but I'd just need to know how to change it whenever I move to another country.

5. Can the email contents be taken from a cell in column X instead of having it in a script itself? simply because if the text needs to change for certain days, it could be done in a cell itself instead of modifying the script.

6. Can column Y generate Email Sent Report, just to let me know that the email went out successfully?

Attaching the file itself below and thanking you very much in advance.

https://docs.google.com/spreadsheets...it?usp=sharing