Definitely worth understanding if redundancy is an option first (and what the package is) before declaring desire for early retirement. Theres a lot of info missing from your post (age, length of service, size of company) that would help with a little more specific advice. Highly likely that they better with redundancy but like stated by other posters its very specific to individual circumstances.
VR works very differently in different organisations. In some large multinationals by the time it all filters down, you may have a department manager with a head count of 140 and a redundancy target of 10 heads. They will bite your friends hand off as the now only have 9 further heads to sort to hit their numbers and your friend will be happy. Win for department head, win for them. The cost may not be of concern to that department head, as it will be exceptionalised (ie not shown) on the p&l for the company for the year which all their bonuses & targets are based on. At the other end of the spectrum if its a small business minding its cash flow and your friend has 40 years service and is only a year off retirement then they might not accept the request for VR.
Only downside of wait and see approach is that they have nothing definite regarding a finish date/ time of year, and can't plan with certainty the things they want to do in the immediate months post finishing work.