I think you are confused......you are half right. Elliot can get his 4th accrued season in 2019 or 2020, so August 6th was a soft deadline. If he does not report by week 10, then he has to report by the deadline in 2020 to get his accrued year in order to reach UFA.
If Zeke does come back by week 10 this season without a new contract, he will get credit for an accrued year. The latest example of this was Joey Galloway in Seattle.
No I am not confused.
He can not accrue his 4th season towards FA in 2019.
Not only does the headline tells you this, this paragraph also says it:
So as long as Elliott reports by Week 10, his fourth year in the NFL counts in 2019, his fifth-year option stays in 2020 and he will be a UFA in 2021. He will have to report by the accrued-season date in 2020 (provided no long-term deal is done by then) or he will risk being a restricted free agent in 2021, with the club still able to place the more expensive but more secure franchise tag on him that year.
He only has one more chance to accrue his 4th year to get unrestricted FA status. That is by showing up in Aug of 2020 under his current deal.
The Galloway situation has nothing to do with accrued years. He had already played 4 seasons in Seattle before holding out (95, 96, 97, 98 and then he held out in 99. Seattle tagged him in 2000 and trade him to us). Galloway's situation has to do with "tolling" a contract. Tolling is basically shifting the terms of the contract forward a year.
What Seattle tried to argue was that in missing games in 1999, Seattle could push his contract forward a year (toll his contract) into 2000, which would mean that technically, Galloway was still under contract in 2000 and his contract hadn't actually expired in 1999. They lost that hearing and then promptly franchise tagged him.