Got my 150k MNEB also, however, I have not upgraded yet. Can you share how much you are getting after a day or couple of days of mining? Just to get an idea how many MNEB you can mine.
Here the information about mining once you upgraded to level 2 or 3Mining Rate: 0.00015 MNEB per BSC Block (~28600 blocks per day)
Mining Rate Per day: 4.23 MNEB (Aprox.)
Mining Duration: 1,000,000,000 BSC Blocks