Two scripts editing a table at the same time?

I have a JSON table stored in a StringValue. This table has every player's name in it, along with a true or false value for each person. One script changes the true/false value for each player depending on whether they are in a certain room or not. The other script adds and removes players if they are joining or leaving the game. Since the table is JSON in a StringValue, I worry that if both scripts run at the same time, one might nullify the others' changes.

Example

1. Script #1 Gets the current table from the JSON StringValue

2. Script #2 Gets the current table from the JSON StringValue

3. Script #1 Changes Player4 to false and submits the new table to the JSON StringValue

4. Script #2 Removes Player9 and submits the new table to the JSON StringValue --This table still remembers Player4 as true, thus nullifying Script #1's changes

So how might I solve this problem? Is there a way to make a globally editable table who's parts can be edited independently of each other?

Scripts can't run at the same time; there is one thread. IF scripts yield then they alternate to different scripts. So as long as each one gets the latest string version often I can't imagine there would be a problem.