Update, these are the final numbers:

Based on the discussion in #245, another proposal may be to have the first testnet fork sooner. All clients are already syncing on YOLOv3, so we could do something like:
Scenario D HF Date
Ropsten 10 Mar 2021
Goerli 17 Mar 2021
Rinkeby 24 Mar 2021
Mainnet 14 Apr 2021
This gives a longer delay between Berlin and London (say London happened mid-July, that's a full 3 months), and it also gives 3 weeks from now for the first testnet to fork.

Potential block numbers:

* Ropsten `9_812_189` (10 Mar 2021)

* Goerli `4_460_644` (17 Mar 2021)

* Rinkeby `8_290_928` (24 Mar 2021)

* Ethereum `12_244_000` (14 Apr 2021)

Math

Original post/conversation below this line.

I think we should discuss Berlin timing again because nothing materialized since the last ACD and this should have higher priority than the London timing. Copy-pasta from discord:

Scenario A: Berlin Mainnet March Rollout

• Ropsten: Feb/24, TimeRemaining 1045200s, CurrentBlock 9_648_023, BlockTime 13.8s, TargetForkBlock 9_723_762 (est.)
• Goerli: Feb/24, TimeRemaining 1045200s, CurrentBlock 4_269_595, BlockTime 15.0s, TargetForkBlock 4_339_275 (est.)
• Rinkeby: Feb/24, TimeRemaining 1045200s, CurrentBlock 8_059_600, BlockTime 15.0s, TargetForkBlock 8_129_280 (est.)
• Kovan: Feb/24, TimeRemaining 1045200s, CurrentBlock 23_434_222, BlockTime 5.3s, TargetForkBlock 23_631_429 (est.)
• (5 weeks buffer)
• Mainnet: Mar/31, TimeRemaining 4072740s, CurrentBlock 11_841_026, BlockTime 13.1s, TargetForkBlock 12_151_922 (est.)

Scenario B: Berlin Staged Testnet Rollout

• Ropsten: Feb/24, TimeRemaining 1045200s, CurrentBlock 9_648_023, BlockTime 13.8s, TargetForkBlock 9_723_762 (est.)
• Goerli: Mar/03, TimeRemaining 1649940s, CurrentBlock 4_269_595, BlockTime 15.0s, TargetForkBlock 4_379_591 (est.)
• Rinkeby: Mar/10, TimeRemaining 2254680s, CurrentBlock 8_059_600, BlockTime 15.0s, TargetForkBlock 8_209_912 (est.)
• Kovan: Mar/17, TimeRemaining 2859480s, CurrentBlock 23_434_222, BlockTime 5.3s, TargetForkBlock 23_973_746 (est.)
• (6 weeks buffer)
• Mainnet: Apr/21, TimeRemaining 5887020s, CurrentBlock 11_841_026, BlockTime 13.1s, TargetForkBlock 12_290_416 (est.)

This is already next week though... can run the numbers again but at some point we would have to make a decision instead of pushing this from meeting to meeting.