diff --git a/data/language/english_uk.txt b/data/language/english_uk.txt
index 837b70305f..6f7217545d 100644
--- a/data/language/english_uk.txt
+++ b/data/language/english_uk.txt
@@ -2441,11 +2441,11 @@ STR_2433    :{BLACK}Vouchers for free {STRINGID}
 STR_2434    :{BLACK}Advertising campaign for {STRINGID}
 STR_2435    :{BLACK}Advertising campaign for {STRINGID}
 STR_2436    :1 week
-STR_2437    :2 weeks
-STR_2438    :3 weeks
-STR_2439    :4 weeks
-STR_2440    :5 weeks
-STR_2441    :6 weeks
+STR_2437    :<not used anymore>
+STR_2438    :<not used anymore>
+STR_2439    :<not used anymore>
+STR_2440    :<not used anymore>
+STR_2441    :<not used anymore>
 STR_2442    :{BLACK}({STRINGID} remaining)
 STR_2443    :{WINDOW_COLOUR_2}Cost per week: {BLACK}{CURRENCY2DP}
 STR_2444    :{WINDOW_COLOUR_2}Total cost: {BLACK}{CURRENCY2DP}
@@ -3811,6 +3811,7 @@ STR_5471    :Scroll map down
 STR_5472    :Scroll map right
 STR_5473    :Cycle day / night
 STR_5474    :Display text on banners in upper case
+STR_5475    :{COMMA16} weeks
 STR_5476    :Hardware
 STR_5477    :Map rendering
 STR_5478    :Controls
diff --git a/src/localisation/string_ids.h b/src/localisation/string_ids.h
index 4bc59a1bb5..b0d85eefc4 100644
--- a/src/localisation/string_ids.h
+++ b/src/localisation/string_ids.h
@@ -1096,11 +1096,6 @@ enum {
 	STR_ADVERTISING_CAMPAIGN_FOR_2 = 2435,
 
 	STR_MARKETING_1_WEEK = 2436,
-	STR_MARKETING_2_WEEKS = 2437,
-	STR_MARKETING_3_WEEKS = 2438,
-	STR_MARKETING_4_WEEKS = 2439,
-	STR_MARKETING_5_WEEKS = 2440,
-	STR_MARKETING_6_WEEKS = 2441,
 	STR_MARKETING_WEEKS_REMAINING = 2442,
 	STR_MARKETING_COST_PER_WEEK = 2443,
 	STR_MARKETING_TOTAL_COST = 2444,
@@ -1824,6 +1819,9 @@ enum {
 
 	STR_CYCLE_DAY_NIGHT = 5473,
 	STR_UPPER_CASE_BANNERS = 5474,
+
+	STR_X_WEEKS = 5475,
+
 	STR_HARDWARE_GROUP = 5476,
 	STR_RENDERING_GROUP = 5477,
 	STR_CONTROLS_GROUP = 5478,
diff --git a/src/windows/new_campaign.c b/src/windows/new_campaign.c
index edf39c2c48..7e2877bc4e 100644
--- a/src/windows/new_campaign.c
+++ b/src/windows/new_campaign.c
@@ -294,8 +294,9 @@ static void window_new_campaign_mousedown(int widgetIndex, rct_window *w, rct_wi
 			);
 		}
 		break;
+	// In RCT2, the maximum was 6 weeks
 	case WIDX_WEEKS_INCREASE_BUTTON:
-		w->campaign.no_weeks = min(w->campaign.no_weeks + 1, 6);
+		w->campaign.no_weeks = min(w->campaign.no_weeks + 1, 12);
 		window_invalidate(w);
 		break;
 	case WIDX_WEEKS_DECREASE_BUTTON:
@@ -366,7 +367,8 @@ static void window_new_campaign_invalidate(rct_window *w)
 	}
 
 	// Set current number of weeks spinner
-	window_new_campaign_widgets[WIDX_WEEKS_SPINNER].image = (STR_MARKETING_1_WEEK - 1) + w->campaign.no_weeks;
+	RCT2_GLOBAL(RCT2_ADDRESS_COMMON_FORMAT_ARGS, uint16) = w->campaign.no_weeks;
+	window_new_campaign_widgets[WIDX_WEEKS_SPINNER].image = w->campaign.no_weeks == 1 ? STR_MARKETING_1_WEEK : STR_X_WEEKS;
 
 	// Enable / disable start button based on ride dropdown
 	w->disabled_widgets &= ~(1 << WIDX_START_BUTTON);