vc-24 is correct.
the effectiveness of the modifications is a condition precedent to the exercise of the warrants, but does not necessarily require the exercise.
a couple of commas (parens even better) prolly woulda helped:
"The exercise of the Series H Warrants[,] upon effectiveness of the modifications and waivers[,] will result in approximately $1.9 million of cash proceeds to Wave."
your interpretation is understandable based on the lack of those commas & the language does make it seem as though the $1.9 flows from the effective date, but IMO, 24/RWK's interpretaion is the accurate one. FWIW.
regards,
SPIN
PS Jean Valjean