Oracle has enough money to cover up everything for ages. Do not expect any kind of public announcement. And remember, WARN notice is only for US..... there is nothing like that in EMEA and APAC.
Will there be layoffs may 31st? yes, definitely.
Will be a carnage like back in sept17? yes, most probaly worse in absolute numbers (stll have to see the final numbers since the new EMEA presale org under CY is still to be finalized next week), even if more "diluted" in time (starting last week of may and ending last week of june) and space (this time EMEA and APAC will be hit much harder than US)
Will be across the board? no, definitely not, Just like back in sept17, this carnage will hit mainly the no more existant System group, now split in c@c under DoK (to be hit in a very light way) and sso under RvG (to be hit very hard, both sales and presales)
Will there be any influence on the stock? nope, in my opinion. The influence will eventually be the Q4 and FY18 results, much worse than expected.