Japan Black over Prooftint Pine Sealer?

I am just finishing off a keyboard bench made out of Radiata Pine and was having a bit of trouble with the finish.

I was planning on staining it black with Feast Watson Prooftint Black, however the test that I did was a bit patchy (and not dark enough). So I was considering staining with Japan Black....

I have already sanded back my bench and sealed it with FW Prooftint Pine Sealer (A Turps based sealer?).

The FW Black Japan instructions say that I sould have sealed the timber with FW Proofseal (spirits based?)....

Does anybody think I will encouter any problems by staining the timber with Japan Black after sealing it with Prooftint Pine Sealer (not Proofseal as per instructions)?

Should I go to the trouble and sand everything back again and seal with Proofseal?

Best I can suggest is to call the company and ask to speak to an expert.

Freecall 1800 252 502

I have spoken to them in the past and found them very helpful.

Regards,
Bob