Recently FAA has changed 61.159 in regards to accepting SIC hours toward ATP aeronautical experience. It used to be that a CPL who works as a SIC on a aircraft that is certified for more than two pilots can apply all hours flown as SIC towards ATP requirements is no longer valid. The new 61.159 c specifically mentioned only Part 135 with approved SIC program. What that means? Well those pilots who plan on working abroad with their CPL may no longer qualify for ATP as there is nothing in the current regs that address that. Moreover those who are working abroad on a validated FAA license would not be able to apply the hours towards FAA ATP and therefore may not be eligible for update to Captain. This new rule came into effect in August so many may not be aware. Now this is only my interpretation. What do you guys think?

https://www.ecfr.gov/current/title-14/chapter-I/subchapter-D/part-61/subpart-G/section-61.159