Buy S&P 500 @ 1840- win at higher risk

Previous Analysis & Trading Signals to watch:
Look to buy S&P 500 @ 1840 if it breaks above resistance, stays above & goes higher, for 30 minutes expiration or less
Look to sell S&P 500 or S&P Futures @ 1840 if it stays below & drops further, for 30 minutes expiration

1840 is a strong resistance as S&P 500 dropped below 1840 resistance most of the time for several days & might drop below again
However, S&P 500 jumped from 1820 to 1840 yesterday, showing a lot of strength
See if 1840 resistance can turn into support today, sell if it fails

Results:
Buy S&P 500 @ 1840- win at higher risk
Buy S&P 500 around 1843 at higher risk as it opened @ 1842, didn't drop below 1843 & went higher
S&P 500 expired @ 1847.84 at 10:30am EST

Sell S&P 500 or S&P Futures @ 1840- invalid
Both broke above 1840 & went higher therefore signal became invalid