The spread (long april18 short may18) has tendency to rise in price @ this period: 
Its backtesting: 
Its price action history: 
Current price action of the spread has stated a higher high and a higher low:
The cumulative delta on the underlier suggesting accumulation:
The caveat for this spread is that there is no aggressive buying from commercials yet:
Also the forward curve showing that there is still carry cost that wheights on price (bear pressure) as the front month (april)still in discount to back month (may) :
