For the speed/climb profile, you need to know what noise procedure is required - NDAP 1 or NDAP 2 (Procedure A or Procedure B in old money).
As far as I am aware, when NDAP 1 is specified (which requires speed to be limited to V2+10 to 20Kt until 3000ft AAL), an ATC statement of "no speed restriction" does not lift this speed limitation for noise control.
Similary, NDAP 2 limits the speed to Vzf +10 to 20Kt until 3000ft AAL...........which can be more than 250Kt in some aircraft so in that case, ATC saying "no speed" is good news provided your company/national authority permits more than 250Kt when below 10,000.
Manchester does not specify which procedure to use, it simply gives an instruction to cross the noise monitoring area at or above 1000ft AAL and operate so as to reduce noise during the climb........Oh, and there is a Pay per decibel fine system. Thus I expect that your company will specify one of the above procedures in the ops manual.
Having said that, it appears that provided you either don't set off the noise monitor or are willing to pay, the height limitations specified only apply to tracks and not to speeds.
Regards,
DFC