diff --git a/goodwe_controller/test_maint28b.py b/goodwe_controller/test_maint28b.py
index 8e87b9f..fb90586 100644
--- a/goodwe_controller/test_maint28b.py
+++ b/goodwe_controller/test_maint28b.py
@@ -335,15 +335,16 @@ def switches(k):
     return sum(1 for x, y in zip(g, g[1:]) if x != y)
 
 
+b_low = min((r["soc_o"] for r in rows), default=0.0)
 print(f"    live try: quarters {[round(q) for q in qs]}, B gives {gb:.2f} kWh, "
-      f"B ends {rows[-1]['soc_o']:.1f} %, give/idle switches A "
+      f"B lowest {b_low:.1f} %, give/idle switches A "
       f"{switches('u')}, B {switches('o')}")
 check("live try: every quarter at or under the aim + 10 W (07d23d2: 6502 and "
       "6499 W against the month peak 6000 W)", max(qs) <= AIM + 10.0)
 check("live try: B gives about its guard part, under 1.5 kWh (1b5f7c9 1.0; "
       "07d23d2 4.6 kW, 25 -> 10 % in 43 min)", gb < 1.5)
-check("live try: B ends at 19.8 % or more (1b5f7c9 19.8)",
-      rows[-1]["soc_o"] >= 19.8)
+check("live try: B's SoC never goes under 19.8 % (1b5f7c9 19.8)",
+      b_low >= 19.8)
 check("live try: give/idle switches of B at most 40 in the 90 min",
       switches("o") <= 40)