Several blocks were rejected by the Bitcoin SV network after the addition, which caused the re-organization in the blockchain's history.
Almost each time someone is trying to produce a very large block on the BSV chain, there’s a reorg. Just an hour ago our Blockchair engine has witnessed a 3-block reorg (I think that's a record)! Blocks #578640–578642 got orphaned by a longer chain because they were too big
Lead developer, Blockchair
Whoops! $BSV has experienced yet another reorg, this time 6 (six!) consecutive blocks were orphaned (#578640–578645), this chain included a 128 MB block #578644 The network was basically stuck for 1.5 hours, and this shows that even 6 confirmations are not enough pic.twitter.com/dwGZmUCqtm
— Nikita Zhavoronkov (@nikzh) April 18, 2019
The large blocks, about which Zhavoronkov writes, are no longer displayed by the blockchain browser, since they are not part of the main chain in which they were located until a certain moment, until they were replaced by another chain, which eventually became dominant.
This is basically exactly the problem the BU gigabock testnet identified. At sizes > 100mb the mempools were so out of sync that blocks were basically transmitted as full blocks.
BSV had ONE 128mb block and it caused a six block reorg. On the BU testnet sustained 128mb blocks caused a total breakdown of the chain where there were so many reorgs that every node had a different view of the state of the blockchain.
Thus, Chris assumes that the problem is caused not by the malicious actions of the network members, but by its functional bug.
This update is noticeable in the background of recent Bitcoin SV delisting campaign, which was started by the number of big exchanges as a reply to lawsuit by Craig Wright, BSV supporter, against anonymous critic.