I predict restaurants, and other small business, to offer employees three 10 hour shifts, or some combination to get under 30 hours per week.
Other employees will fill in the daily gaps, or work two 10 hour shifts on the week end.
Heck, a temp agency will find you those extra 10 hours as employers scramble to get everyone under 30 hours
For large companies, I forecast more clerical employees will face a 20-25 hour week. Two clericals @ 20 will replace one at 40 plus