Another option is to start the buyback, and announce while still buying, after the company has already completed the majority of what they plan to buy. That way S/P increases but not fast enough to affect companies plan too much. Otherwise, since most of us have stressed that we are here to stay, the shares could dry up. If I think that my shares might be going to the benefit of the company over the long term, I might be more willing to part with a few.
There are other ways it can be done over time. An effecient way is to allocate a percentage of profit to the re-purchase and retirement of shares. As an example: say 5% of profits each month to purchase shares at current market prices. That not only reduces the float, but also adds strength to the stock with the increased volume, which in turn causes the PPS to increase.
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