Cancel vs modify solicitation in For Beginners Only Posted December 24, 2019 · Report reply On 12/23/2019 at 10:02 AM, joel hoffman said: Major changes to the PWS or MAJOR change to the payment terms might warrant cancellation. Also may depend upon the timing of the changes in the solicitation period. Also depends upon how many various types of changes, like described above are collectively or simultaneously occurring. Ah, but what is major? I would say anything that adds to the requirements placed on the contractor is major; anything that subtracts from the requirements placed on the contractor is also major; and anything that might adversely affect the contractor or contractor's rights is also major. Most modifications will fit in one of those categories.